Spotnet import, header backfill, staging and counter grouping, faster search

Spotnet (CONCEPT D29):
- Index free.pt fully and import spots with their descriptions, categories
  and NZBs; a spot renames its release, since Spotnet names are more
  trustworthy than names derived from subjects.
- Find passwords in spot descriptions too, and tell "needs a password we
  have" from "needs a password we don't have".

Content inspection:
- List the contents of 7z (.7z.001) archives, SFV sets, nicovideo uploads
  and other archive-like files; mark yEncBin .bin containers as encrypted.
- Take real names from yEnc headers for randomly named files, and merge
  uploads that were split across posts.

Storage (D31, D32):
- Store segment lists zstd-compressed behind the FileStore accessor.
- group:backfill indexes older headers at low priority and pauses when
  the NVMe or HDD part of the database gets too large.

Grouping (D35, D36):
- Lone header segments wait in staged_segments until a second segment of
  their file arrives, which drops the per-article junk binaries.
- Counter grouping joins random-subject uploads by poster, [i/M] counter,
  part count and day.

Search and maintenance (D33, D34):
- A trigram-indexed search_text column, smaller indexes, estimated stats.
- Passes that clean up nonsense names; weekly index maintenance; GC budgets
  per kind.
- Web UI: grey out stale results while a search runs and cancel superseded
  requests. Count only up to 1,000 matches for the page, which made filter
  clicks take seconds (Newznab keeps the 10,000 cap).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

commands/ReleaseMergeSplit.ts

@@ -0,0 +1,21 @@
+import { BaseCommand, flags } from '@adonisjs/core/ace'
+import { CommandOptions } from '@adonisjs/core/types/ace'
+import ReleaseMergeService from '#services/ReleaseMergeService'
+
+/** Merges uploads split per poster (gc:scheduler also does this every sweep). */
+export default class ReleaseMergeSplit extends BaseCommand {
+  public static commandName = 'release:merge-split'
+  public static description = 'Merges releases of one upload that was posted under a different poster per file.'
+
+  public static options: CommandOptions = {
+    startApp: true,
+  }
+
+  @flags.boolean({ description: 'Only count them' })
+  declare dryRun: boolean
+
+  public async run() {
+    const { names, releases } = await ReleaseMergeService.mergeSplitPosts({ dryRun: this.dryRun })
+    this.logger.info(`${names} split uploads; ${releases} releases ${this.dryRun ? 'would be' : ''} merged into their first.`)
+  }
+}